cc: Remove DrawQuad::IterateResoruces

cc/quads/io_surface_draw_quad.h

Index: cc/quads/io_surface_draw_quad.h
diff --git a/cc/quads/io_surface_draw_quad.h b/cc/quads/io_surface_draw_quad.h
index 2c77905cd7999db94638d4a5fab31489eb317979..4a8a072c61cd75623e0aaec3c7e6c7915d7d869d 100644
--- a/cc/quads/io_surface_draw_quad.h
+++ b/cc/quads/io_surface_draw_quad.h
@@ -40,14 +40,17 @@ class CC_EXPORT IOSurfaceDrawQuad : public DrawQuad {
               Orientation orientation);
 
   gfx::Size io_surface_size;
-  unsigned io_surface_resource_id;
   Orientation orientation;
 
-  void IterateResources(const ResourceIteratorCallback& callback) override;
+  ResourceId io_surface_resource_id() const {
+    return resources.ids[kIOSurfaceResourceIdIndex];
+  }
 
   static const IOSurfaceDrawQuad* MaterialCast(const DrawQuad*);
 
  private:
+  static const size_t kIOSurfaceResourceIdIndex = 0;
+
   void ExtendValue(base::trace_event::TracedValue* value) const override;
 };